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The move: An explosive movement that incorporates all the major muscles of your core.

Works on: Core stability, power and strength.

Difficulty: Easy to intermediate.

Precautions: Use caution if you have any low back pain.

Setup: Grab a medicine ball preferably with handles or a rope attached. You can also use a dumbbell and just hold it on one end. Sit down and lift your legs up off the ground and lean back so your weight is all centered underneath your glutes.

Steps: Without letting your feet touch the ground, slam the ball down by your right hip then without resting bring it back to your left hip. Continue this repetition for as long as you can. Go until your form starts to break down.

Repetitions: Perform 3 sets for as long as you can.

Options: You can keep your feet on the ground if this movement is too difficult. The faster the movement is, the harder it becomes. You can also sit on top of a Bosu ball or a stability disc to increase difficulty.

Each week, Firehouse Fitness features members of the San Diego Fire-Rescue Department demonstrating exercises and stretching techniques that can be incorporated into almost any fitness routine.